hey all i got a 85 iroc with a 385 tpi the car runs fine has good vac of 18,hg
timing of 6 degs and fuel pressure of 48 psi.
the car takes off good pulls good and has no smoke at all. the thing i notice was when in gear it feels like at has a small lopey cam. here are the specs
214 intake and 218 exhaust dur @.50 and 448 lift on both sides with a lsa of 114. 1.5 roller rockers mild intake porting.
its not a bad shake you can slightly feel in in the hole car and the rpms will jump around 150 +/-. i do have 24 lbs injectors and a 85 vett chip so i could get 22lbs signal. has any one had the same thing happen to them or do i have something wrong. i was just thinking with a cam that small it should not do it. but i can live with it . would like anyones

 

If it only does it at idle and in gear maybe your idle rpms are too low.

 

the idle is about at 850.

 

from my experience on a basic 350

rpms should not fluxate that much. Shouldnt be more then 50-60.


by your fuel specs, I'm guessing its running a tad rich, which might be the problem. I say get a custom chip made and see if it still does it.

 

well i found my problem i had 1 and only 1 rocker arm just a little to tight.
adjusted it and now all is well.

 

the 85 vette came with 24lb injectors. but, had 36 psi fuel rail pressure. with 48 psi you have increased the injector size, therefor the ecu in closed loop is trying to adjust the BLM's but, it is probably out of range. try lowering the rail pressure to the 36 and see what happens. 22lb started in 86 with 43.5 psi rail pressure